1. Field of the invention
The present invention concerns a control device for high-voltage equipment including a display panel.
To be more precise, it concerns a control device for high-voltage equipment including:
a computer adapted to receive status information from the equipment via at least one transmission cable, and PA1 a display system including a support device carrying on its visible face an equipment status mimic diagram associated with indicator lamps. PA1 from a centralized control room from which commands are sent to the computer, PA1 in a local operation mode from a local cabinet from which the control buttons of the display panel can be operated, the computer being operational and the computer and the display panel being accommodated in the cabinet, and PA1 in an emergency operation mode from a local cabinet, the computer not being operational. PA1 by a display system that is totally independent of the computer, i.e. the control buttons and the indicator lamps of which are physically separate from the computer; the display system is then energized by a polarity independent of that of the computer and fed by a status information transmission cable from the equipment which is also independent of that of the computer; operation in the emergency mode from the independent display system is then no problem and this solution is therefore reliable although costly. PA1 a display system entirely integrated into the computer, i.e. the control buttons and the indicator lamps of which are physically integrated into the computer; it is then fed directly by the computer but should the latter fail the display system is no longer operational; this solution is therefore relatively economical but it is not reliable for the operator since in the event of computer failure operation in the emergency mode is not possible.
2. Description of the Prior Art
There are three conventional modes of operation of control devices for high-voltage equipment:
The operating mode is typically selected by a three-position switch.
The digital computer assures the automatic control functions, for example interlocking in accordance with the status of other high-voltage equipment, the density of the dielectric gas in the various compartments in the case of metal-clad or other equipment, etc.
The computer replaces the electromechanical relay devices used previously and offers the possibility of evolution towards more sophisticated functions, for example surveillance of the status of the equipment and the possibility of communicating with a higher control and command level via a communication bus.
However, this technology is greeted with some reluctance by some operators because of the necessity to review maintenance methods and more importantly the fear that a major computer failure would render the system totally inoperable and operation impossible.
At present, the display panel function is implemented by two different types of systems:
The control device of the invention solves these problems, being less costly than the control devices including the first type of display system and more reliable than those incorporating the second type of display system. It offers an optimal reliability/cost trade-off.